Linking form with function: AFRL’s flex team drives future tech capabilities for the warfighter

Dr. Christopher Tabor discusses potential applications of liquid metal alloys. A member of the Flexible Materials and Processes team at the Air Force Research Laboratory’s Materials and Manufacturing Directorate, Tabor’s team is exploring possible uses of liquid metals for stretchable and reconfigurable electronics for the Air Force. (U.S. Air Force photo / David Dixon)

A member of the Flexible Materials and Processes team at the Air Force Research Laboratory’s Materials and Manufacturing Directorate exhibits an additively manufactured electrical circuit embedded in a flexible material substrate. The flex team is exploring novel ways to use 3-D printing technology to create next generation flexible hybrid technologies for the Air Force. (U.S. Air Force photo / Marisa Alia-Novobilski)

One of the most notable, recent projects by the Flexible Materials and Processes team is the transition of 3-D printed conformal antennas to enable Link-16 radio communication on the MQ-9 reaper platform. The team’s expertise in additive manufacturing and functional materials enabled them to create a quick-turn solution to meet a communication need for the Air National Guard. (Courtesy photo)

WRIGHT-PATTERSON AIR FORCE BASE, Ohio --Led by Dr. Benji Maruyama and comprised of a cadre of energetic, innovative, high-performing scientists and engineers, the members of the Air Force Research Laboratory’s Flexible Materials and Processing Team take comprehension of soft matter to a new level.

“We take a basic understanding of soft, flexible materials and use this as a foundation to build functional devices,” said Maruyama. “These include flexible batteries, sensors, hybrid electronic devices and more. Much of what we’re working on now the people in the field don’t even know they need yet. We’re building competencies for the future.”

Perhaps one of the most diverse research teams in the Materials and Manufacturing Directorate, the members of the flex team have backgrounds ranging from the basic sciences such as chemistry, physics and electronics to engineering and applied disciplines across the research spectrum. Many researchers on the team split their time between flexible materials and other directorate research teams, enabling greater cross-functional research applications. The team’s two military members provide a direct tie to the warfighter, helping ensure work remains focused on Air Force critical needs.

“We do a lot with the warfighter, trying to understand and anticipate the near and far-term needs. The interface between humans and machines is a big driver of our research,” said Maruyama.

Exploiting the benefits of additive technology, nanomaterials and autonomous research platforms while leveraging partnerships with industry and academia, the team masterminds a future-focused material research portfolio dedicated to ensuring the Air Force has the most advanced technology for the fight.

Though the projects within the team are diverse, all fall inside of three primary research themes. These are the human-machine interface, development of compliant and functional materials, and processing and novel device packaging and integration of materials for sensing, power and communications.

One focus in the human-machine interface arena is on the next-generation of wearable sensors for human performance monitoring. Commercial products, such as activity trackers and other smart watches, focus primarily on sensing movement and heartrate and have limited sensing modalities and durability, limiting their use in many challenging warfighter operational environments. The ability to sense physiological changes in a pilot’s stress or fatigue levels through sweat or electrolytes on the surface of skin, for example, can potentially eliminate harmful situations before they have a chance to occur in flight.

“Integration and packaging challenges are at the heart of enabling wearable devices for Air Force environments,” said Maruyama. “In conjunction with our human performance directorate, universities, other labs and industry we are working to develop innovative solutions such as foldable batteries and stretchable interconnects to create better technologies.”

Another area of work has the team exploring adaptive materials, or those with the ability to sense and respond to external stimuli, through novel design tools. One way they are doing this is through a high-tech application of origami, the ancient Japanese art of paper folding.

“Origami is a way of changing shapes very precisely,” said Dr. Philip Buskohl, a materials and mechanics researcher in the group. “We're using origami to amplify the mechanical response of materials that shrink or expand when exposed to light, heat, humidity or other stimuli. Additionally, the origami structure can serve as a means for deployment, which is relevant for antennas, space assets and temporary shelters.”

While much of the team’s work focuses on basic research technologies for future applications, building a cadre of subject matter experts has enabled them to rapidly respond to some near-term Air Force needs as well. One of these successes is the transition of 3-D printed conformal antennas to enable Link-16 radio communication on the MQ-9 reaper platform in conjunction with the Air National Guard and other industry partners.

“The MQ-9 effort is one of the higher profile projects to come out of our branch,” said Dr. Abigail Juhl, a materials research engineer who focuses her work on additive manufacturing of tunable acoustic materials. “AFRL spent over a decade building competency in the printing of conformal antenna, so when the problem came along, within months we were able to create a solution to meet the needs.”

The team’s research is also showing commercialization potential in the field of flexible batteries, and they are in the process of acquiring a patent for their in-house developed technologies.

“We’ve developed ways to make flexible batteries safer, and there is interest in pilot production by industry,” said Maruyama. “A lot of time the failure in a flexible battery occurs when the current collector fails. We’ve developed two different technologies in this area—a foldable nanotube current collector and a 3-D printable, high temperature separator. We are exploring possible transition partners.”

Though the flexible materials and processing team is developing what could be game-changing technologies for the Air Force, there are a number of challenges they work to address as they focus efforts on a unique research portfolio.

For Jeremy Ward, one of the newest members of the team, one challenge is understanding who within AFRL and the larger defense research community is working in similar areas.

“It is important that we engage with researchers outside of our team, to include industry, universities and other federal labs,” he said.

Additionally, there is a misunderstanding of what the lab is capable of delivering and what others think can be accomplished.

“Sometimes there is an assumption that a technology is beyond the point where it has truly evolved. Oftentimes, the communities that can benefit from the technology that we are developing do not understand this gap. Part of our job is to help communicate a realistic timeline for the research and development activities,” said Ward.

Added to this is the excitement, energy and motivation of many members of the team to do more.

“Our lab cultures people who are ‘go-getters,’” said Matthew Dalton. “When do we hit our limit? You have to know what is strategic to pursue versus going after all that is possible.”

There are also complications when it comes to manpower.

“Finding the ‘right’ people with the expertise in our field is tough. We work a lot with post-docs and students, and we have proposals and funding to bring people on our team, but it’s often hard to get people with the skill sets we need to see the great opportunities in government research,” said Juhl.

Nevertheless, the flexible materials and processing team understands their role in ensuring the Air Force has the technology it needs as it moves into the future. Though much of their work focuses on basic research, the ability to evolve research focus in a nonlinear fashion enables them to address needs initially not anticipated, using knowledge gained during the initial exploratory process.

“We have to anticipate the battles the warfighters will face in the future, and we’re taking huge risks every time,” said Maruyama. “We have to know the opportunity space and become the experts.”

“It’s exciting, it’s challenging. It’s the best part of being on this team,” he concluded.